Spi 91-372-3 Feeler Gauge 0.019 in Parallel Leaf 12 in

Product Description

The SPI 91-372-3 is a parallel-leaf feeler gauge used to measure precise gaps and clearances in mechanical assemblies. Manufactured from high carbon steel, this gauge measures 0.019 inches thick, 0.5 inches wide, and 12 inches long. The parallel leaf design maintains a consistent thickness from end to end, providing reliable, repeatable measurements across the full length of the blade. This type of gauge is a standard hand tool used by HVAC technicians, mechanics, and other trade professionals when setting valve clearances, checking spark plug gaps, measuring bearing tolerances, and verifying component fit during installation or service.

Feeler gauges are used across a wide range of service and installation tasks where precise gap measurement is required. The 12-inch blade length accommodates both standard and hard-to-reach measurement points. The 0.019-inch thickness is a commonly referenced gap specification in burner orifice alignment, fan blade clearance checks, and mechanical equipment calibration. This gauge is suited for residential and light commercial service environments and is typically found in the toolboxes of licensed HVAC technicians, plumbers, and general equipment mechanics.

Key Features

• Parallel leaf design maintains uniform 0.019-inch thickness along the full 12-inch length
• High carbon steel construction for durability and resistance to bending under normal use
• 0.5-inch blade width provides a stable measurement surface
• 12-inch blade length reaches deep or recessed gap locations
• Single-leaf format for direct, uncomplicated gap checks

Compatibility

Designed as a standard 0.019-inch feeler gauge blade suitable for general mechanical and HVAC service applications requiring precise gap measurement.

Installation Notes

Feeler gauges do not require installation but should be handled and stored carefully to prevent bending or surface corrosion that could affect measurement accuracy. Always power down or de-energize equipment before inserting a gauge into a live assembly. Apply only light, consistent hand pressure when seating the blade in a gap — forcing the blade can cause permanent deformation and render the gauge inaccurate. Clean the blade after each use and store it flat to maintain its calibrated thickness.